Dividing up profits between investors

[Connor Janda]

My brother and I are looking to begin our adventure into the world of real estate investing using the BRRRR method. I have a small amount in investment savings (Let's say I have enough to help with half the rehab costs). I have little equity elsewhere since i rent. My brother has a similar amount in savings as I do but has a home with >1/3 of the mortgage paid off. The home has appreciated in value over the past few years.

We have not found a particular place to purchase yet. But my brother has discussed getting a home equity loan on his current home in order to make a sizable down payment. A leader stated that his interest on the loan would be fixed at his current rate which is pretty good. 

Has anyone every used this method for purchasing a home and splitting the profits? If so, are there any suggestions or cautions you might give? How did you divide the profits between each other and did that method seem fair? Thank you for you help!